Behringer Bi-/Dual-Phase
This is the Behringer clone of the vintage Mu-Tron® Bi-Phase phaser. It got two phaser lines and two LFOs. you may use them as parallel (stereo in to stereo out), or one input with two phasers in parallel as mono to stereo configuration, or two phasers in series (mono). The second phaser named "B" may use its own or the LFO of phaser "A" in normal or inverted configuration. The later is useful for wide stereo FXs.
The sound character is much transparent like a Small Stone due to the 4 phaser stages and not as beefy and emphased as phaser with more stages (6 or 9 or 12 stages).